Micrometer sized platelet-like particles of bismuth titanate (Bi₄Ti₃O₁₂) are prepared successfully by the calcination of a mixed-precursor in air. The mixed precursor is precipitated under microwave-hydrothermal (MH) treatment via dissolution-recrystallization kinetics. The mixed precursor is precipitated in-situ by giving MH treatment (at 200°C, 200 psi, and 30 min hold time) to the hydrolysed slurry containing Bi and Ti cations. The slurry was prepared by adding 20% aqueous KOH precipitant solution to a well-mixed stoichiometric nitrate solution containing Bi and Ti cations. XRD results revealed that the as-dried precursor consisted of a homogeneous mixture of non-crystalline particles of Bi₂O₃ and TiO₂. The calcination of the as-dried precursor at 700°C/2 h in air resulted in the formation of micron sized platelet like single-phase Bi₄Ti₃O₁₂ powders having orthorhombic structure.